Turtlerock Forum

Hi, has anyone had any experience of these parts that are now being made , or at least sold from China?
Like this,
http://www.ebay.com/itm/10PCS-OP-AMP-IC ... 3a74a95661
Or this
http://www.ebay.com/itm/1PCS-Signetics- ... 4adab8174c
I bought some of the Auditronics modules that were going recently here on Turtlerock and there are a mix of different brands of 5534s in them. Also, the A 30 output cards have 741s in them and I would like to replace them with 5534s.
Now, I'm not sure I buy into the theory that Signetics 5534s are the best ( I have no A/B test experience of this to know for sure), but I do want to get all the channels to match, and replace the 741s on the output cards.
So, should I just buy a new tube of TI 5534s and replace all the chips with them? Or track down Signetics NOS?
Any suggestions or thoughts welcome.
Cheers,

I'd just get TI 5534A

Funny. I bought two 501 modules a while back, but not together. The second one was advertised as having Signetics as if that was a big thing. As I haven't racked them yet I don't know, but I suppose any modern 5534 might be better than the originals that were in them.

My MCI JH600 came loaded with Signetics 5534's and 5532's. I have encountered all the comments about signetic's apparent sonic superiority, but I can't say I really notice a difference between an all signetic's loaded channel and one with a very large chunk replaced by modern TI equivalents.

If there is a difference, it is minuscule compared to other changes that have been made (replacing DBX 202 driven VCA faders with analogue ones, replacing 5534 summing amps with 990c's, recapping it).

Thanks everyone,I'll go with the TI's. I think I already have some around here somewhere...
One of the 110 modules has Signetics, guess I'll ebay those chips for a stupid vintage price....
Just kidding.
Cheers, Paul

The Sig' s do measure and sound better to my ears.

They actually measure better? Better than TI's? Now that is interesting.
Cheers,
Paul

Paul Maybury wrote:Hi, has anyone had any experience of these parts that are now being made , or at least sold from China?
Like this,
http://www.ebay.com/itm/10PCS-OP-AMP-IC ... 3a74a95661
Or this
http://www.ebay.com/itm/1PCS-Signetics- ... 4adab8174c
I bought some of the Auditronics modules that were going recently here on Turtlerock and there are a mix of different brands of 5534s in them. Also, the A 30 output cards have 741s in them and I would like to replace them with 5534s.
Now, I'm not sure I buy into the theory that Signetics 5534s are the best ( I have no A/B test experience of this to know for sure), but I do want to get all the channels to match, and replace the 741s on the output cards.
So, should I just buy a new tube of TI 5534s and replace all the chips with them? Or track down Signetics NOS?
Any suggestions or thoughts welcome.
Cheers,

As mentioned alsewhere, the TI 5534 is fine, they will be a significant upgrade to the 741.
The 5534 needs a 22pF compenasation cap across pins 5 / 8 for UG operation.

You can also go for one of the many newer higher performance opamps that are lower distortion than 5534 and
also unity gain stable. Most are only available in SMT packages so you will need to use SMT to DIP adaptors which
for non techs can be a PITA.

WRT opamp sound and distortion this is worth a read-

http://www.sg-acoustics.ch/analogue_aud ... ortion.pdf

For the non technical, it shows that the implementation makes a big difference - in most cases. A very big distortion contributor is common mode and that is mainly affected by the surrounding circuit design.

cheers